Wait... is it possible that I hear an M3 owner... bringing up drag times and top speeds... Isn't the M3 known for its handling and poise rather than drag racing on the street?

I agree with all your points but aren't we comparing apples to oranges (someone mentioned, "do you like apples or sunglasses")?
I know the OP is debating which car to get but, I believe the spyder and the Z4 would be more on par for a comparison?